The air filters with which this invention is concerned comprise foraminated filter media arranged in each of a plurality of V-cells in a Vee-Cell module. The individual V-cells are defined by expanded metal with the filter media releasably attached to the interior of the expanded metal in each individual V-cell. The Vee-Cell module extends across a large exhaust conduit in an air handling system to collect airborne waste material generated by a manufacturing facility. The use of Vee-Cell modules is widely used in the textile industry, and others.
The cleaning of the filter media in the V-cells is important to the efficient operation of the air handling system. Several attempts have been made to provide apparatus for effectively cleaning the filter media. For example, U.S. Pat. No. 3,166,391, issued Jan. 19, 1965 to Keser for FILTER CLEANING DEVICE FOR AIR EXHAUST SYSTEMS AND THE LIKE, discloses an apparatus that blows compressed air against the downstream side of filter media in V-cells and collects waste blown from the media in collection tubes on the upstream side of the filter media. The compressed air is delivered to the downstream side of the filter media through pipes that are moved in a reciprocating path across the filter media by a reversible motor. The pipes are moved to the top of the V-cells and stopped while the motor reverses itself to lower the pipes to the bottom of the V-cells.
Pneumafil Corporation makes an apparatus for cleaning the filter media in parallel panels. The Pneumafil apparatus uses a reversible motor to power an indexing mechanism that directs nozzles up and down and in and out of the filter media on parallel panels to direct a negative pressure or vacuum against the upstream side of the filter media. The reversible motor stops, of course, each time it changes direction.
Bahnson Parks Cramer makes an apparatus for cleaning the filter media in Vee-Cell modules. Again, the apparatus is powered by a reversible motor that stops and starts as it reciprocates the apparatus across the surface of the filter media to direct a vacuum against the upstream side of the filter media.
In all of the prior art devices known to applicant for cleaning the filter media in Vee-Cell modules, the apparatus that moves the air nozzles across the filter media is powered by a reversible motor. The motor is operatively connected to the nozzles and moves the nozzles in one direction from a first position to a second position, where the motor stops momentarily as it shifts into the reverse mode. The motor then restarts and moves the nozzles in the opposite direction across the filter media to return the nozzles to the first position.
In most installations, the working environment creates so much dust and airborne waste that it is necessary to continuously clean the filter media during normal operation. The repetitive stopping and starting of the power source interrupts the cleaning cycle and contributes to equipment failure and undesirable interruption of service with a consequent decrease in product quality.